Motor fuel products



Patent ed June 11, 1935 UNITED STATES PATENT F F I C E 2,004,560 MOTORFUEL PRODUCTS Robert E. Wilson, Chicago, Ill., assignor, by mesneassignments, to Gasoline Antioxidant Company, Wilmington, Del., acorporation of Delaware No Drawing. Application September 18, 1931,Serial No. 563,674

12 Claims.

The present invention relates to improvements in motor fuel products,more particularly, motor fuel products of the eifective metallo-organicanti-knock type incorporating the highly or detonation-inhibitingagents, such as the commonly employed tetra-ethyl lead.

In the producti knock pressure cracking having, when treated to for use,a

more particularl pounds, such as selenium, tin, arsenic, and

on of motor fuels of high antiof heavy hydrocarbon oils, and make themsatisfactory suflicient stability with regard to gum y, themetallo-organic comthe alkyl compounds of lead,

antimony, iron carbonyl and the like. Of these, the most commonlyemployed is tetra-ethyl lead, generally in admixture with an alkylhalide,

such as ethylene dibromide or ethylene chlorbromide. These admixtures ofalkyl hali des and tetra ethyl lead are well and are referred to in thisapplication as ethyl fluid or tetra ethyl lead solusolution, in general,usually about 40% compound.

contains from 25 to 50% and of the active metallo-organic I have foundthat the addition .of an anti-knock compound, and particularly ofmetallo-organic compounds such as tetra-ethyl lead, even in the theamount of gum tests therefor. This tendency to increased gum formation,and particularly on storage, may be indicated by an accelerated testknown as the oxygen absorption induction test, which we prefer toconduct in ticle by Voorhees Proceedings of the January 3, 1929,

the manner described in an arand Eisinger, published in the AmericanPetroleum Institute, page 170. In accordance with this test, the amountof oxygen absorbed under certain standard meters of the gas conditionsby 100 cubic centioline or motor fuel distillate at a temperature ofabout 210 atmosphere under a pressure .of 2.5 atmospheres is determined,and the period prior to the time at which the rate of absorption becomes1 cc. per

F. with an oxygen The gasoline or motor fuel distillates to which theanti-knockmaterial is added 100 lbs. gauge an generally under pressuresof 250 to 900 lbs. and at temperatures ordinarily not exceeding 950 F.Such products, when subjected ties in this respect, their oxygenabsorption induction period is ordinarily above 350 minutes, However,when as the concentrated tetra-ethyl lead solution known as ethyl isadded, there is a marked decrease in their oxygen absorption inductionperiod, the decrease generally being by' more than to 12% and frequentlyby as much as 25 to 30% or even more. The decrease in the oxygeninduction period is indicative of a subthe usual evaporation tests.

The following table illustrates the effect upon the gum or resinformation properties of gasoline or motor fuel distillates of theaddition of sufficient proportions of a concentrated solution oftetra-ethyl lead, generally called ethyl fluid or tetra ethyl leadsolution in proportions to impart to the product an octane number of atleast 74.

Oxygen induction period 1 in es 'I'he'proportion of tion containing 40to quired to impart the to such fuels may vary from 0.5 to lon of thegasoline distillate material.

ethyl fluid or ethyl solu- 50% of tetra-ethyl lead redesired anti-knockrating 4 cc. per gal- It has now been discovered that this deteriorationor greater instability with respect to gum formation and resinificationby the presence of minute quantities of such organo-metallic compoundsadded to secure an improved anti-knock rating may be decreased orcompletely counteracted by incorporating in the product containing theorgano-metallic compound small proportions of stabilizing aromaticcompounds having a substituting group from the class including thehydroxyl, amino and substituted amino groups. The proportions of suchcompounds added may vary from 0.001% or somewhat less to 0.005% or even0.01%, based on the weight of gasoline product, or from 0.025 to 0.27grams per cubic centimeter of tetra-ethyl lead or other organo-metalliccompound employed. Such compounds are inert with respect to theorgano-metallic compound employed and to the aliphatic halide compoundswhich usually accompany it. The compounds which I have foundparticularly suitable for use are the condensed polynuclear compoundshaving a substituting group selected from the class consisting of thehydroxyl and amino groups, such as alpha-naphthol, beta-naphthol, alphanaphthylamine, beta naphthylamine, the hydrogenated naphthylamines, suchas tetra-hydronaphthylamine, dihydroxynaphthalene, amino-naphthol, andthe like.

For example, in a particular case, a gasoline or motor fuel distillatederived from a high pressure cracking process, after sweeteningtreatment, was found to have a satisfactory stability with respect togum formation, having an oxygen absorption induction period of 690 andshowing on the usual gum test, less than 1 mg. gum per 100 cc. andshowing substantially no development of gum forming constituents onstorage. On the addition of a minute amount of ethyl fluid (less than 1cc. per gallon), the oxygen absorption induction period dropped to 200minutes and it was found that gum developed on storage and on the usualgum test, the amount of gum formed rose to an excessive figure, beinggreater than 5 mg. per 100 cc. On the addition thereto of smallproportions of alpha-naphthol, this deterioration was largelycounteracted and the material stabilized to a satisfactory extent withrespect to gum and resin formation. Thus, the addition of 0.002%alpha-naphthol increased the oxygen absorption induction period to 490and the addition of 0.004% of alpha-naphthol increased it to 590, thesefigures being indicative of satisfactory gum stability. Other specificcompounds of the class hereinbefore set forth produced similar results,largely or completely counteracting the action of the organo-metalliccompound and restoring the stability of the fuel product.

I may also employ, to counteract the deleterious effect of suchorgano-metallic compounds upon hydrocarbon distillates of this charactervarious polyhydroxy aromatic compounds such as hydroquinone, resorcinol,catechol, pyrogallol, nicotine pyrogallate, amyl gallate, and the like;and amino phenols, such as para-aminophenol, diaminophenol, para andortho-methyl-aminophenols, dimethyl-aminophenol, benzyl-aminophenols,hydroxyazobenzene, butyl and isopropyl-aminophenols,dihydroxy-diphenylamine, paraphenetidine, and the like. The proportionsemployed are within the ranges hereinbefore stated, the

, specific proportion required varying with the specific character ofthe hydrocarbon distillate and the proportionof the organo-metalliccompound employed. The specific proportion of any ingredigum formation,

ent required may be readily determined by the application of the oxygenabsorption test, hereinbefore referred to.

It has been found that a satisfactory method of introducing theinhibiting agent is by incorporating it in the concentrated solution ofthe organo-metallic compound. In such case, it is in general necessaryto modify the solvent employed in the concentrated solution of theorganometallic compound therein of the requisite amounts, varying from10 to 25%, of the desired inhibiting substance. Thus, instead of asolvent consisting substantially entirely of kerosene or other similarfluid, I may employ a solvent consisting of a mixture of kerosene andbenzol containing 25 to 50% of the latter, a mixture of kerosene andacetone containing from 20 to 50% of acetone, or a mixture of kerosene,acetone and benzol in approximately equal proportions. A suitableconcentrated fluid or solution for the purpose contains 60% tetraethyllead, 25% ethylene dibromide and the remainder, the mixed solvent of thecharacter hereinbefore set forth. With this is incorporated 0.025 to0.27 grams of the anti-oxidant or aromatic reducing agent per cubiccentimeter of tetra-ethyl lead; for example, I may employ 0.132 to 0.266and preferably about 0.175 to 0.20 grams of alpha-naphthol per cubiccentimeter of tetraethyl lead in the fluid. This concentrated fluid isthen added to the hydrocarbon motor fuel distillate of low anti-knockvalue in proportion to impart to it the desired anti-knock rating,generally an octane rating of '14 or higher. The proportion of theconcentrated fluid required for this purpose may vary from 0.5 cc. to 4or 5 cc. per gallon, but, in general, with cracked hydrocarbondistillate of satisfactory gum stability, as indicated in general by anoxygen absorption induction period of at least 300, but with a lowantiknock rating, from 0.5 to 1.5 cc. are sufficient to impartanti-knock ratings of '74 octane number or higher, equivalent to theaddition of 3 cc. or more standard ethyl fluid to a straight-run Mid-Continent gasoline.

What I regard as new, letters Patent, is:

1; A motor fuel product comprising principally an unsaturatedhydrocarbon distillate boiling within the gasoline boiling range andinitially stable with respect to gum formation, an added smallproportion of knock suppressing agent, the addition of which results inan impaired stability of the motor fuel with respect to gum formation,and a small amount of an amino hydroxy benzene whereby said impairmentof gum stability is corrected.

2. The process of restoring the gum stability of a cracked gasolineinitially stable with respect to gum formation but whose gum stabilityhas been impaired by the addition of a tetra ethyl lead solution as aknock suppressing agent, comprising adding to said gasoline a smallamount of an amino hydroxy benzene wherein one amino hydrogen has beensubstituted by a hydrocarbon radical.

3. A motor fuel product comprising a cracked hydrocarbon distillateboiling within the gasoline boiling range and initially stable withrespect to as indicated by an induction period of at least 300 minutes;a small proportion of tetra ethyl lead as a knock suppressing agent, theaddition of which results in an impairment of the stability of the motorfuel with respect to gum formation; and a small amount, not exceedingand desire to secure by to permit of incorporation tetra ethyl leadsolution as a paired gum stability not more than 0.01% of a hydrocarbonsubstituted-amino hydroxy benzene whereby said impairment of gumstability is substantially inhibited.

5. The method of restoring the gum stability of a motor fuel containingcracked gasoline which has been impaired by the addition of less than 1compound wherein one amino hydrogen has been substituted by ahydrocarbon radical.

6. The method of preventing tetra ethyl lead impairing the gum stabilityof an initially gum stable motor fuel containing cracked gasoline, whichcomprises incorporating in said motor fuel an amino hydroxy benzenecompound wherein one amino hydrogen has been substituted by ahydrocarbon radical.

7. The method of preventing tetra ethyl lead solution from impairing thegum stability of an initially gum stable motor fuel containing crackedgasoline, which comprises incorporating in said motor fuel not more than0.01% of an aryl substituted-amino hydrow benzene.

8. The

gasoline, which comprises incorporating in said motor fuel a smallamount of a benzylaminophenol.

9. The method of preventing tetra ethyl lead solution from impairing thegum stability of an motor fuel not more than about 0.01% of parabenzylaminophenol.

10. A motor fuel product of an unsaturated within the gasoline boilingrange and initially suppressing agent, the addition of which results inan impaired stability with respect to gum formation; and a small amountof a benzylaminophenol whereby said impairment of gum stability iscorrected.

11. The method of preventing tetra ethyl lead solution from impairingthe gum stability of an initially gum stable motor fuel containingcracked gasoline, which comprises incorporating in said motor fuel asmall amount of an amino hydroxy benzene wherein an amino hydrogen hasbeen substituted by an alkyl radical.

12. A motor fuel product comprising principally an unsaturatedhydrocarbon distillate boiling within the gasoline boiling range andinitially stable with respect to gum formation as indicated by aninduction period of at least 300 minutes, a small proportion of tetraethyl lead solution as a knock suppressing agent, the addition of whichresults in an impaired stability with respect to gum formation, and asmall amount of a methyl-amino phenol to inhibit said impairment of gumstability.

ROBERT E. WILSON.

